This invention relates generally to a sensor device and more particularly to a micro sensor device which may be employed in a variety of sensor applications to monitor, sense, or measure a concentration of a material within a sample.
There are numerous applications in which a device is used to monitor or detect a concentration of material within a substance. For example, it may be required to know the concentration of a chemical in a sample of material such as knowing the concentration of sodium, calcium, or some other chemical composition in a sample. Monitoring or detecting a concentration of a substance typically requires a set up of relatively complex, sensitive, and expensive equipment or instrumentation. Sometimes space requirements make it difficult to use the set up of complex equipment and it would be advantageous to have equipment which has small dimensions and is easily transportable. Additionally, such complex equipment may not provide results which are of a high resolution.
One known and important application for monitoring a concentration of a material within a sample deals with checking blood glucose for diabetics. There are at least two known techniques for monitoring blood glucose levels in humans. The first technique is invasive which involves extracting samples with the use of needles or syringes. Typically, for the invasive method, a patient employs a small lancet device which is used to prick or puncture a finger. Blood is then collected onto a strip which has incorporated therein a chemical reagent. The strip is then placed inside of a device that optically reads the chemical reaction of the blood on the strip and converts this to a blood glucose level. It has been found very important to control glucose levels in diabetics to reduce any complications associated with diabetes. Many samples or finger pricks may be required to be taken for analysis during the course of a day. Self monitoring of blood glucose by a patient is therefor very important in the treatment of diabetes. Since finger pricking or lancing is required for self monitoring levels of glucose in a patient, many patients avoid this because it is painful and inconvenient. Therefore, a less invasive procedure would be desirable. The second technique is known as noninvasive and does not require that the skin be punctured. The noninvasive technique typically involves a devices which uses near infrared light to detect blood glucose levels. These devices measure a glucose concentration in blood or an organism's tissue by use of an optical device without the need to collect blood or fracturing a part of the organism's tissue. Although these devices use noninvasive methods, in that no blood is collected, none of these devices have been commercially accepted or viable.
The present invention is designed to obviate and overcome many of the disadvantages and shortcomings associated with the prior use of complex testing and monitoring equipment. Additionally, the present invention is simple to use, provides extremely quick results and high resolution, and is easily transportable. The present invention uses relatively inexpensive components which results in a commercially viable product. Further, the micro sensor device of the present invention is relatively noninvasive since it does not require the drawing of blood and provides immediate results which does not require related blood processing such as centrifugation, storage, transportation, and other time consuming testing.